But the idea of a runtime app is something I've actually been thinking about and I think there's value there.

@omz is there anyway to use the shared "app group" functionality of iOS as Pythonista2 and Pythonista3 do to allow either the template, or an ancillary app made by you to act as a dedicated testing app - no editing abilities, just a container to run the app. Perhaps you could specify which script to run in the global iOS settings, or from within Pythonista2/3. You could really quickly make edits in the main apps, and test in the ancillary app to get a close idea of how quickly your app launches without all the editor cruft etc, so it would be built from the template. You could even charge money for it, and it would (i assume) be a minimal amount of work for you to implement since most of it is already done in the form of the template!
And looking to the future - once the issues with split-screen multitasking are remedied by Apple, imagine being able to have pythonista2/3 on one half of the screen and the testing app on another - it would be like a real development workflow!!